1. Field of the Invention
The invention relates to a housing for receiving electrotechnical components.
2. Description of the Related Art
A generic housing is described in WO 03/001393 A2, which is in the name of the Applicant. Here in the transitional area between the housing shells forming the housing and joined together in a form-fitting manner a sealing element is arranged for sealing the inner chamber from the external environment. According to one embodiment variant of said housing a double-walled casing portion has been proposed in order to improve its sensitivity to impact and breaking strength. The band or ring-like sealing element is clamped between the inner wall and the outer wall of the double-walled casing portion, so that it exerts a sealing force perpendicular to the sealing faces, in particular to the wall webs, which sealing force needs to be absorbed or picked up by the wall webs. The sealing effect achievable by this embodiment and the fitting of the sealing element are only satisfactory to a limited extent in this case.
GB 2 064 879 A describes a housing of a display and/or control unit which is designed for marine applications, in particular for use on yachts. The housing of said display and/or control unit is formed by three external components or three elements which can be accessed from the outside. In particular, a shell-like front element, a shell-like rear wall element and a board-like intermediate element are arranged on top of one another in a sandwich-like structure so that as a whole they form the outer borders of the display and/or control unit. The board-like intermediate element is provided for mounting a printed board for the electronic components and has in its circumferential section, which defines a central portion of the casing surface of the housing, an essentially I-shaped cross-sectional contour. In two circumferentially running grooves of said board-like intermediate element a cord-like sealing element is inserted. The outermost delimiting web of said board-like intermediate part for mounting the electronic components thus forms an outer delimiting face in the casing surface of the housing of the display and/or control unit. The robustness and sealing effect achievable by this configuration is not entirely satisfactory for industrial applications.
JP 2011-190892 A discloses a sealing element which is arranged between a first and a further housing part and seals the transitional gap between the two housing elements. The sealing element comprises a carrier element with an approximately H-shaped cross section. Said sealing element is made of plastic and mounts a pair of sealing elements made from a rubber-like material. Said sealing elements made of rubber-like material are mounted integrally in the two mounting depressions of the H-like carrier element. From said sealing elements sealing lips project respectively over the groove-like mounting recesses and lip-like rubber material projects over the bordering edges of the carrier element made of hard plastic. In this way a small sealing element is created which makes it unnecessary to form grooves in the housing parts and which is intended to achieve the simple handling of the sealing element as well as a stable sealing effect. The sealing lips projecting from the carrier element enable an effective seal between grooveless plate or housing elements placed flat on top of one another. A seal between shell-like housing parts, the wall webs of which face one another, cannot be achieved satisfactorily by the described sealing element.
DE 10 2006 006 386 A1 describes a further generic housing which is also in the name of the applicant. In this case a housing is proposed for electronic devices, in particular for mobile hand-controlled devices of an industrial control. Said housing comprises a half-shell lower housing part and a half-shell upper housing part, the edge-side wall sections of which in the assembled state form the casing surface of the housing. A continuously extending or partly interrupted inner wall runs spaced apart essentially constantly from an outer wall forming the casing surface of the housing. Furthermore, a sealing element is arranged lying at least partly between the outer wall and the inner wall to avoid the penetration of the solid and liquid materials. In this case in a portion of the sealing element facing the inner side of the outer wall at least two lip-like sealing extensions are formed, which each bear on the inner faces of the lower housing part and the upper housing part and exert elastic pretensioning on said inner faces, from the inner wall in outwards direction. In this way the robustness of the housing is improved, the assembly of the housing parts with the sealing element lying between the inner and outer wall is relatively complicated however. Furthermore, the sealing elements required are comparatively expensive and complex to shape.